1. Field of the Invention
This invention relates to a smoke filter material, and more particularly, to a smoke filter material especially useful for tobacco products.
2. Description of the Prior Art
Generally, smoke, e.g., as produced by smoking cigarettes, cigars and pipe tobaccos, is made up of gaseous components together with minute liquid droplets and solid particles suspended therein. Contained in such tobacco smoke are some components which are considered to be hazardous to the smoker's health. Therefore, various kinds of smoke filters have been proposed and put to practical use in an effort to remove such components.
Commonly used materials for smoke filtering are fiber aggregates (hereinafter referred to as fiber matrices), and various adsorbents are generally used in combination therewith. Conventional filter materials, however, have not been fully satisfactory, e.g., with respect to filtration efficiency, as well as other properties.
Smoke filter materials that previously have been used include fiber matrices, such as cellulose acetate or pulp fiber matrices. Also, activated carbon, zeolite, silica gel, ion exchange resin, etc., in granular form, have been used as adsorbents within the filter matrix. Many of these conventional adsorbents have a large active surface area and are gas adsorbents, but are disadvantageous in one or more respects. For example, activated carbon has the drawback that, during smoking, it emits the characteristic odor of active-carbon. Moreover, its adsorptive affinity for nicotine, tar and the like is low.